Research

As Chengze Li, I am an assistant professor at the School of Computing and Information Sciences, Saint Francis University. My research interests include Computational Comics and Manga, Computational Photography, and other fun stuff at the intersection of graphics and AI.

Featured Projects

SIGGRAPH 2026

See-through: Single-image Layer Decomposition for Anime Characters

Jian Lin, Chengze Li, Haoyun Qin, Kwun Wang Chan, Yanghua Jin, Hanyuan Liu, Stephen Chun Wang Choy, Xueting Liu

ACM SIGGRAPH 2026 Conference Papers

Automatically decomposes a single anime illustration into fully inpainted, semantically distinct layers with inferred drawing order, turning static art into manipulatable 2.5D models.

PDF (acm.org) ↗ arXiv ↗

ACM MM 2025

ColorDiffuser: Video Colorization with Pretrained Text-to-Image Diffusion Models

Hanyuan Liu, Minshan Xie, Jinbo Xing, Chengze Li, Chi-Sing Leung, Tien-Tsin Wong

ACM International Conference on Multimedia

Adapts a pretrained text-to-image diffusion model for video colorization using Color Propagation Attention for reference-based color refinement and an Alternated Sampling Strategy for bidirectional temporal consistency across frames.

Project ↗ PDF (acm.org) ↗ arXiv ↗ Code ↗

VC 2025

Instance-guided Anime Editing with a Curated Large-scale Dataset

Jian Lin, Chengze Li, Xueting Liu, Zhongping Ge

The Visual Computer

Introduces a 100k-image cartoon instance segmentation dataset and model, powering character-level editing applications like 3D Ken Burns parallax, style editing, and puppet animation.

Project ↗ PDF (springer.com) ↗ arXiv ↗ Code ↗

Pacific Graphics 2024

A Contrastive Unified Encoding Framework for Sticker Style Editing

Zhihong Ni, Chengze Li, Hanyuan Liu, Xueting Liu, Tien-Tsin Wong, Zhenkun Wen, Huisi Wu

Pacific Conference on Computer Graphics and Applications

A contrastive learning framework that encodes each sticker pack's visual style into a unified latent space, enabling seamless style transfer, interpolation, and mixing across arbitrary sticker sets.

PDF (eg.org) ↗

AAAI 2022

End-to-End Line Drawing Vectorization

Hanyuan Liu, Chengze Li, Xueting Liu, Tien-Tsin Wong

AAAI Conference on Artificial Intelligence

Proposes an end-to-end Transformer-based method that directly converts raster line drawings to vector strokes in a single step, eliminating error-prone intermediate segmentation via automatic stroke-by-stroke tracing.

PDF (aaai.org) ↗

SIGGRAPH 2021

Seamless Manga Inpainting with Semantics Awareness

Minshan Xie, Menghan Xia, Xueting Liu, Chengze Li, Tien-Tsin Wong

ACM Transactions on Graphics

Addresses manga inpainting after balloon/text removal by separating the task into semantic inpainting and appearance synthesis, with disentangled structural line and screentone features for better content understanding.

PDF (acm.org) ↗ Code ↗

CVPR 2021

User-Guided Line Art Flat Filling With Split Filling Mechanism

Lvmin Zhang, Chengze Li, Edgar Simo-Serra, Yi Ji, Tien-Tsin Wong, Chunping Liu

IEEE/CVF Conference on Computer Vision and Pattern Recognition

A Split Filling Mechanism for user-guided line art flat filling that explicitly computes color scribble influence areas to prevent leakage between regions, while leveraging data-driven color generation learned from over a million illustrations.

Project ↗ PDF (cvf.com) ↗ Code ↗

ECCV 2020

Erasing Appearance Preservation in Optimization-Based Smoothing

Lvmin Zhang, Chengze Li, Yi Ji, Chunping Liu, Tien-Tsin Wong

European Conference on Computer Vision

Shows that partially erasing the appearance preservation term in optimization-based image smoothing facilitates better results, formulating automatic erasing as a 0-1 knapsack problem applicable to texture removal, intrinsic decomposition, and material editing.

Project ↗ PDF (springer.com) ↗ Code ↗

SIGGRAPH Asia 2020

Manga Filling Style Conversion with Screentone Variational Autoencoder

Minshan Xie, Chengze Li, Xueting Liu, Tien-Tsin Wong

ACM Transactions on Graphics

Proposes ScreenVAE to map screened manga to an interpolative intermediate domain, unifying the properties of screentone and color filling for bidirectional translation between Western color comics and Japanese manga styles.

PDF (acm.org) ↗ Code ↗

SIGGRAPH Asia 2018

Two-stage Sketch Colorization

Lvmin Zhang, Chengze Li, Tien-Tsin Wong, Yi Ji, Chunping Liu

ACM Transactions on Graphics

A two-stage framework for sketch colorization: the drafting stage splashes varied colors, then the refinement stage detects and fixes artifacts like color distortion and blurring. Powers the popular style2paints tool.

PDF (acm.org) ↗ Code ↗

SIGGRAPH 2017

Deep Extraction of Manga Structural Lines

Chengze Li, Xueting Liu, Tien-Tsin Wong

ACM Transactions on Graphics

A CNN-based approach to extract structural lines from pattern-rich manga, suppressing arbitrary screentone patterns regardless of regularity, scale, or complexity, with no assumptions on pattern types.

PDF (acm.org) ↗ Code ↗

All Publications

Jian Lin, Chengze Li, Haoyun Qin, Kwun Wang Chan, Yanghua Jin, Hanyuan Liu, Stephen Chun Wang Choy, Xueting Liu. "See-through: Single-image Layer Decomposition for Anime Characters," ACM SIGGRAPH 2026 Conference Papers (SIGGRAPH), 2026. PDF (acm.org) arXiv BibTeX

Minshan Xie, Jian Lin, Hanyuan Liu, Chengze Li, Tien-Tsin Wong. "Advancing Manga Analysis: Comprehensive Segmentation Annotations for the Manga109 Dataset," IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2025. PDF (cvf.com) BibTeX

Hanyuan Liu, Chengze Li, Minshan Xie, Zhenni Wang, Jiawen Liang, Chi-Sing Leung, Tien-Tsin Wong. "BlueNeg: A 35mm Negative Film Dataset for Restoring Channel-Heterogeneous Deterioration," IEEE/CVF International Conference on Computer Vision (ICCV), 2025. PDF (thecvf.com) Dataset Project BibTeX

Xueting Liu, Zibo Zhang, Hao Xia, Chengze Li, Huisi Wu. "Calligraphic Guideline Generation via Contour-guided Brush Fitting," International Conference on Graphics and Image Processing (ICGIP), 2025. BibTeX

Huisi Wu, Hao Meng, Chengze Li, Xueting Liu, Zhenkun Wen, Tong-Yee Lee. "Cartoon Animation Outpainting With Region-Guided Motion Inference," IEEE Transactions on Visualization and Computer Graphics (TVCG), 2025. PDF (ieee.org) BibTeX

Hanyuan Liu, Chengze Li, Tien-Tsin Wong, Xueting Liu. "ChromaFlow: End-to-End Flow Matching for Efficient Video Colorization," SIGGRAPH Asia Technical Communications (SA TC), 2025. PDF (acm.org) Code BibTeX

Hanyuan Liu, Minshan Xie, Jinbo Xing, Chengze Li, Chi-Sing Leung, Tien-Tsin Wong. "ColorDiffuser: Video Colorization with Pretrained Text-to-Image Diffusion Models," ACM International Conference on Multimedia (ACM MM), 2025. Project PDF (acm.org) arXiv Code BibTeX

Jian Lin, Chengze Li, Xueting Liu, Zhongping Ge. "Instance-guided Anime Editing with a Curated Large-scale Dataset," The Visual Computer (VC), 2025. Project PDF (springer.com) arXiv Code BibTeX

Hao Xia, Xueting Liu, Chengze Li, Zhenkun Wen, Huisi Wu. "Robust Character Stroke Segmentation for Diverse Fonts via Contour Matching and Chain Propagation," IEEE International Conference on Image Processing (ICIP), 2025. PDF (ieee.org) BibTeX

Minshan Xie, Menghan Xia, Chengze Li, Xueting Liu, Tien-Tsin Wong. "Screentone-Preserved Manga Retargeting," Computer Graphics Forum (CGF), 2025. PDF (wiley.com) arXiv BibTeX

Minshan Xie, Hanyuan Liu, Chengze Li, Tien-Tsin Wong. "Synchronized Multi-Frame Diffusion for Temporally Consistent Video Stylization," Computer Graphics Forum (CGF), 2025. PDF (wiley.com) arXiv BibTeX

Jian Lin, Chengze Li, Haoyun Qin, Hanyuan Liu, Xueting Liu, Xin Ma, Cunjian Chen, Tien-Tsin Wong. "Trajectory-guided Anime Video Synthesis via Effective Motion Learning," Pacific Conference on Computer Graphics and Applications (Pacific Graphics), 2025. PDF (eg.org) BibTeX

Zhihong Ni, Chengze Li, Hanyuan Liu, Xueting Liu, Tien-Tsin Wong, Zhenkun Wen, Huisi Wu. "A Contrastive Unified Encoding Framework for Sticker Style Editing," Pacific Conference on Computer Graphics and Applications (Pacific Graphics), 2024. PDF (eg.org) BibTeX

Wenpeng Xiao, Cheng Xu, Jiajie Mai, Xuemiao Xu, Yue Li, Chengze Li, Xueting Liu, Shengfeng He. "Appearance-Preserved Portrait-to-Anime Translation via Proxy-Guided Domain Adaptation," IEEE Transactions on Visualization and Computer Graphics (TVCG), 2024. PDF (ieee.org) Code BibTeX

Zhenhua Ou, Xueting Liu, Chengze Li, Zhenkun Wen, Ping Li, Zhijian Gao, Huisi Wu. "Body Part Segmentation of Anime Characters," Computer Animation and Virtual Worlds (CAVW), 2024. PDF (wiley.com) BibTeX

Haoyun Qin, Jian Lin, Hanyuan Liu, Xueting Liu, Chengze Li. "Hyperstroke: A Novel High-quality Stroke Representation for Assistive Artistic Drawing," SIGGRAPH Asia Technical Communications (SA TC), 2024. PDF (acm.org) arXiv BibTeX

Ziheng Ma, Chengze Li, Xueting Liu, Huisi Wu, Zhenkun Wen. "Separating Shading and Reflectance From Cartoon Illustrations," IEEE Transactions on Visualization and Computer Graphics (TVCG), 2024. PDF (ieee.org) BibTeX

Huisi Wu, Ziheng Ma, Wenliang Wu, Xueting Liu, Chengze Li, Zhenkun Wen. "Shading-Guided Manga Screening From Reference," IEEE Transactions on Visualization and Computer Graphics (TVCG), 2024. PDF (ieee.org) BibTeX

Jian Lin, Xueting Liu, Chengze Li, Minshan Xie, Tien-Tsin Wong. "SKETCH2MANGA: Shaded Manga Screening from Sketch with Diffusion Models," IEEE International Conference on Image Processing (ICIP), 2024. PDF (ieee.org) arXiv BibTeX

Yinghua Liu, Chengze Li, Xueting Liu, Huisi Wu, Zhenkun Wen. "AddCR: a Data-driven Cartoon Remastering," The Visual Computer (VC), 2023. PDF (springer.com) BibTeX

Hanyuan Liu, Jinbo Xing, Minshan Xie, Chengze Li, Tien-Tsin Wong. "Improved Diffusion-based Image Colorization via Piggybacked Models," arXiv Preprint (arXiv), 2023. Project arXiv BibTeX

Minshan Xie, Chengze Li, Tien-Tsin Wong. "Manga Rescreening with Interpretable Screentone Representation," arXiv Preprint (arXiv), 2023. arXiv BibTeX

Chenshu Xu, Xuemiao Xu, Nanxuan Zhao, Weiwei Cai, Huaidong Zhang, Chengze Li, Xueting Liu. "Panel-Page-Aware Comic Genre Understanding," IEEE Transactions on Image Processing (TIP), 2023. PDF (ieee.org) BibTeX

Hanyuan Liu, Chengze Li, Xueting Liu, Tien-Tsin Wong. "End-to-End Line Drawing Vectorization," AAAI Conference on Artificial Intelligence (AAAI), 2022. PDF (aaai.org) BibTeX

Hanyuan Liu, Chengze Li, Xueting Liu, Tien-Tsin Wong. "Neural Recognition of Dashed Curves with Gestalt Law of Continuity," IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2022. PDF (ieee.org) BibTeX

Xueting Liu, Wenliang Wu, Chengze Li, Yifan Li, Huisi Wu. "Reference-guided Structure-aware Deep Sketch Colorization for Cartoons," Computational Visual Media (CVM), 2022. PDF (springer.com) BibTeX

Zibo Zhang, Xueting Liu, Chengze Li, Huisi Wu, Zhenkun Wen. "Shape-aware Stroke Segmentation for Calligraphic Characters," Computational Visual Media (CVM), 2022. BibTeX

Zibo Zhang, Xueting Liu, Chengze Li, Huisi Wu, Zhenkun Wen. "Vectorizing Line Drawings of Arbitrary Thickness via Boundary-based Topology Reconstruction," Computer Graphics Forum (CGF), 2022. PDF (wiley.com) BibTeX

Huisi Wu, Yifan Li, Xueting Liu, Chengze Li, Wenliang Wu. "Deep Texture Cartoonization via Unsupervised Appearance Regularization," Computers & Graphics (CG), 2021. PDF (elsevier.com) BibTeX

Zhuming Zhang, Menghan Xia, Xueting Liu, Chengze Li, Tien-Tsin Wong. "Invertible Tone Mapping with Selectable Styles," arXiv Preprint (arXiv), 2021. arXiv BibTeX

Lvmin Zhang, Chengze Li. "Screenshots from Screen Photography," ACM SIGGRAPH Posters (SIGGRAPH Posters), 2021. PDF (acm.org) BibTeX

Minshan Xie, Menghan Xia, Xueting Liu, Chengze Li, Tien-Tsin Wong. "Seamless Manga Inpainting with Semantics Awareness," ACM Transactions on Graphics (SIGGRAPH), 2021. PDF (acm.org) Code BibTeX

Lvmin Zhang, Chengze Li, Edgar Simo-Serra, Yi Ji, Tien-Tsin Wong, Chunping Liu. "User-Guided Line Art Flat Filling With Split Filling Mechanism," IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2021. Project PDF (cvf.com) Code BibTeX

Lvmin Zhang, Chengze Li, Yi Ji, Chunping Liu, Tien-Tsin Wong. "Erasing Appearance Preservation in Optimization-Based Smoothing," European Conference on Computer Vision (ECCV), 2020. Project PDF (springer.com) Code BibTeX

Minshan Xie, Chengze Li, Xueting Liu, Tien-Tsin Wong. "Manga Filling Style Conversion with Screentone Variational Autoencoder," ACM Transactions on Graphics (SIGGRAPH Asia), 2020. PDF (acm.org) Code BibTeX

Xinghong Hu, Xueting Liu, Zhuming Zhang, Menghan Xia, Chengze Li, Tien-Tsin Wong. "Colorblind-shareable Videos by Synthesizing Temporal-coherent Polynomial Coefficients," ACM Transactions on Graphics (SIGGRAPH), 2019. PDF (acm.org) BibTeX

Yi Guo, Zhuming Zhang, Chu Han, Wenbo Hu, Chengze Li, Tien-Tsin Wong. "Deep Line Drawing Vectorization via Line Subdivision and Topology Reconstruction," Computer Graphics Forum (CGF), 2019. PDF (wiley.com) BibTeX

Lvmin Zhang, Chengze Li, Tien-Tsin Wong, Yi Ji, Chunping Liu. "Two-stage Sketch Colorization," ACM Transactions on Graphics (SIGGRAPH Asia), 2018. PDF (acm.org) Code BibTeX

Xueting Liu, Chengze Li, Tien-Tsin Wong. "Boundary-aware Texture Region Segmentation from Manga," Computational Visual Media (CVM), 2017. PDF (springer.com) BibTeX

Chengze Li, Xueting Liu, Tien-Tsin Wong. "Deep Extraction of Manga Structural Lines," ACM Transactions on Graphics (SIGGRAPH), 2017. PDF (acm.org) Code BibTeX

Xueting Liu, Chengze Li, Haichao Zhu, Tien-Tsin Wong, Xuemiao Xu. "Text-aware Balloon Extraction from Manga," The Visual Computer (VC), 2016. PDF (springer.com) BibTeX

Chengze Li, Xiaoyun Yuan, Juyong Zhang, Xiaoxin Lv, Lu Fang, Oscar C. Au. "Learning to Beautify Facial Image," IEEE International Conference on Multimedia and Expo Workshops (ICME Workshops), 2014. PDF (ieee.org) BibTeX